What are confirmed, pending, and permanent codes?

A pending code will not turn on your check engine light and indicates that a system on your vehicle is behaving abnormally, but not so much as to mean there is an actual problem.

For example a temperature sensor might have a normal operating range of 90-110 degrees, but 80-120 degrees is considered acceptable. Once the sensor starts to read 85 degrees it is outside of the "normal" range but isn't a problem yet, so a pending code will appear.

Confirmed Codes

A confirmed code indicates that a vehicle system is experiencing an issue requiring your attention. In the temperature sensor example above, once the reading drops below 80 or above 120 degrees the vehicle would then throw a confirmed code as well.

Permanent Codes

Permanent codes are a special type introduced more recently which can not be cleared using a scan tool. If you have a permanent code the vehicle will clear it itself once the cause has been addressed and sufficient data has been gathered by driving under different conditions (idling, stop and go, highway)